1. Field of the Disclosure
This disclosure relates to a blasting device for producing a premixed abrasive slurry jet used for cutting the material in the field of high pressure water jet, especially a kind of blasting device for producing premixed abrasive slurry jets.
2. Discussion of the Background Art
At present, in the case of cutting some hard material, the predominant approach is to depend on the high pressure to drive the slurry carrying the mixture of water and sand in the cutting device to eject at a high speed, which would realize the cutting intention.
The conventional cutting device, e.g. the blasting device for producing a premixed abrasive slurry jet disclosed in the section 10.2.3 of the publication of High Pressure Water Jet Technology and Its Application (Shengxiong Xue et al., High Pressure Water Jet Technology and Its Application, China Machine Press, 1998.8). As shown in the FIG. 1, the device comprises hydraulic oil tank 1, high pressure pass 3 constituted with high pressure pump 2, oil return pass 4, electromagnetic change-over valve 5 connected to high pressure pass 3 and oil return pass 4, two hydraulic cylinders 6 in parallel with the top connected to electromagnetic change-over valve 5, hydraulic cylinder 6 formed by the cylinder block 7 and piston 8 which separates the cylinder block 7 into two sealed cavities. The bottom of the hydraulic cylinder 6 connects a slurry feeding pass 9 which contains a slurry case 10 and a diaphragm pump 11 and connects with a nozzle pass 12. During the cutting, the piston 8 in the cylinder block 7 would slide up and down in the hydraulic cylinder 6 under the high pressure hydraulic oil or slurry. The up-and-down movement would fill the slurry into the cavity or drive the slurry to jet out of the nozzle 12.
In the conventional device, the slurry to perform the cutting operation mainly consists of water and sand. While the piston 8 moves up and down in the cylinder block 7, the friction between the external surface of piston 8 and the inner surface of cylinder block 7 will cause abrasion. Such abrasion makes the originally two sealed cavities to lose the seal and then does not work any more. Therefore, a new hydraulic cylinder will be needed. However, the sliding friction would be essential between the piston 8 and the cylinder block 7. Such a consideration presents a strict requirement for the inner wall of the cylinder block 7. Therefore, the conventional hydraulic cylinder has some disadvantage, such as short life, difficult maintenance and high cost.